Angel

In the beginning there was Liam, eldest son of a well-to-do Irish family and feckless layabout around town. He drank himself stupid, was interested in anything with a skirt, and whored around. Your basic waste of space, never to make anything of himself. However, one night, he had an argument with his father, stormed out, got pissed out of his tree, and met a blonde vampiress going by the name of Darla.

Post siring, he decided to slaughter his family out of a petty grudge against his father (the chip on his shoulder was somewhat large). His little sister said that he resembled an angel, and thus he became Angelus, the demon with the face of an angel. He went on to gain the sobriquet 'the Scourge of Europe', a somewhat showy if fitting title, considering Angelus was one truly nasty, twisted bastard. But we love him anyway.

In time, he sired childer. The first was Penn, a Puritan lad, who had absolutely no sense of style or originality about him. In the 1800s he decided to drive a girl who had visions mad and slaughter her family, and then sired her. Drusilla if you're wondering. One night Dru came across a nice young lad by the name of William, who tended to get spurned in love, and wrote bloody awful poetry. She drank his blood, then went off into a daze. Angelus ended up having to do the actual siring, as far as we can tell. Anyway, they went on their merry way for a while.

Then comes the idiotic bit. Never meddle in the affairs of the Rom, especially the Kalderash. It's really not a wise idea, because they know such spells as the ensouling one.(which was silly enough to include a get-out clause of 'achieve true happiness, bye-bye soul')

The poor lad got himself a conscience and a severe guilt complex. After being rejected by his sire, he buggered off to America. Hotels are involved in this somewhere. However, on a Hellmouth in California, two hours drive from LA, he met a slayer, fought on her side for a while, lost the soul after having sex with her, went on a bit of a rampage, got sent to hell, regained it after coming back from hell, spent a lot of time brooding, decided that he and the slayer couldn't work in a month of sundays, and moved himself to LA. You don't want to know how much angst was involved, trust me.

In LA, he set up a detective agency after gaining one link to the PTB in the form of an Irish half-demon by the name of Doyle. And a secretary named Cordelia, ex-prom queen of Sunnydale and ex-slayerette. Her ability to make bad coffee has yet to be surpassed. Doyle was killed. Cordelia gained the migraine visions from the PTB. And complains about it on a regular basis.

Look, we are getting somewhere, honest...

An ex-watcher turned demon hunter turned up on his doorstep tracking a demon. After helping with the case, Wesley moved in and became part of Angel Investigations.

You want more? Dear god. This is just the 'basic history' section. Go look somewhere else for the pointers.